High-energy traumatic spondyloptosis at T8-T9 with complete spinal cord injury: a case report.

Introduction: Spondyloptosis, the most severe form of spondylolisthesis, involves complete (>100%) anterior or posterior displacement of one vertebra over the subjacent segment, resulting in total anatomical dislocation. Typically caused by high-energy trauma, it leads to severe spinal instability, bony fragment intrusion into the canal, and significant neurological deficits. This report presents a representative case of T8-T9 spondyloptosis with complete spinal cord injury [American Spinal Injury Association (ASIA) Impairment Scale Grade A]to analyze its injury features, surgical approach, and clinical outcomes. Patient concerns: A 61-year-old female was admitted to the hospital presenting with severe thoracodorsal pain and complete paralysis of both lower extremities for 8 h following a crushing injury by a heavy object. The patient exhibited intense back pain and a pronounced thoracic kyphotic deformity. Complete loss of motor and sensory function was observed below the xiphoid process level. Imaging studies revealed complete dissociation between the T8 and T9 vertebral bodies. The distal fracture segment (T9) was displaced posteriorly and superiorly, resulting in impaction of the anterior margin of the T9 vertebral body against the spinous process of T8. Complete fractures with rotational displacement were noted in the posterior elements, including the pedicles and facet joints at the T8-T9 level. Primary diagnosis: T8-T9 spondyloptosis with complete spinal cord injury (ASIA A). Interventions: On the ninth day post-injury, the patient underwent posterior open reduction, laminectomy for decompression, inter-laminar bone grafting, and segmental instrumentation with internal fixation of the thoracic fracture. Outcomes: The patient's postoperative vital signs remained stable. Imaging revealed satisfactory correction of the thoracolumbar deformity, adequate positioning of the internal fixation hardware, near-complete restoration of the spinal physiological curvature, satisfactory fracture reduction, reconstitution of the spinal canal morphology, and appropriate alignment of the implants, all of which met preoperative expectations. Conclusion: This case represents the first reported instance of T8-T9 spondyloptosis with complete spinal cord injury resulting from high-energy trauma. The management of high-energy thoracolumbar fractures necessitates an in-depth understanding of the injury mechanism to formulate an individualized surgical strategy.